Metal culvert.



w. T. SHANNON. METAL GULVB RT.

APPLICATION FILED JULY 19,1912.

v 1,040,442. I Patented 0ct.8, 1912.

UNITED STATES PATENT OFFICE.

WILLIAM '1. SHANNON, or cmcrivna'rr, onro.

METAL CULVERT.

Specification of Letters Patent.

Patented Oct 8, 1912.

Application filed July 19, 1912. Serial No. 710,347.

this character have been open are that means have not been provided for securing the sheet metal sections one to another quickly and in a manner such that the locking means would not be rusted out by the action of the moisture.

The object of my invention is a culvert provided with a means for readily securing the sections together, which notonly does not weaken the sections and render them pervious to rust, but strengthens them.

A metal culvert embodying my invention is illustrated in the accompanying drawings,

in which Figure 1 is a perspective view of the bottom plates of two sections ofa culvert embodying my invention. Fig. 2 is a similar view, but with the arched cover plates in position upon the bottom plates. Fig. 3 is a sectional view taken upon line 33 of Fig. 2. Fig. 4 is a longitudinal sectional view taken upon line 4-4 of Fig. 2.

Each section of the culvert consists of a bottom plate A and an arched cover plate B. The bottom plates have adjacent to each edge trough shaped grooves a a, of a width approximately equal to the thickness of the corrugated cover plates. Each of the trough shaped grooves a a terminates in a downturned flange (1 a. The trough shaped groove and the down-turned flange upon each edge of a bottom plate, form an ogee curve along each edge of said plate. The arched cover plates are of a span equal to the distance between the grooves in the bottom plates. Preferably the arched plates are corrugated to give them rigidity.

being seated in the groove In assembling the parts to form a culvert the bottom plates A arelocked one to another by placing them end to end and forcing the ogee curves of one plate into the ogee curves of an adjacent plate, as shown in Figs. 1 and 4. The arched plates are then engaged with the bottom plates by forcing their ends into the trough shaped grooves.

in the bottom plates. When the arched plates are so positioned upon the bottom plates, a pressure, downward upon the cover plates, such as is exerted by earth placed 0 upon the cover plates, tends to spread the cover plates, and to place the bottom plates under tension. This because of the ogee character of the flanges on the bottom plates,

puts the bottom plates under tension, and

thus firmly closes the joints between adjacent plates of the bottom. The trough shaped groove and the down-turned flange upon each edge of a bottom plate stiflens the edges of the plate and aflords an ef- 7 ficient resistance to the outward pressure upon the edges of the cover plates. The bottom plates being secured together by an integral locking means avoids the use of rivetswith the consequent punching of the 7.

plates, and hence there is no metal which is left uncoated. Thereforethere is no part of the metal sections which are liable to become rusted. The cover plates are locked together at their ends by the interlapping of the corru ations, as shown in' Fig. 4..

What I claim is:

A culvert composed of sheet metal sections, each section consisting of an arched upper plate and a flat bottom plate, each bot-tom plate having near each edge a trough shaped groove with its outer wall terminatmg in a down-turned flange, said grooves and flanges of adjacent bottom sections being fitted into one another to lock said bottom plates together, and the arched plates s WILLIAM T. SHANNON. Witnesses:

WALTER F. MURRAY,

W. THORNTON Boonn'r.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Iatcnts, Washington, I 0. 

